CHEM-C311 Analytical Chemistry LaboratoryJuly 7, 2011The main purpose of this experiment is to identify an unknown organic acid by conducting various experiments to determine the acid’s unique properties. By determining selected constant properties of the unknown and then comparing these properties to the constant properties of known substances, it is possible to identify an unknown substance. The properties used to identify the unknown must be intensive, or independent of amount. Both chemical properties and physical properties are intensive properties used in determining the identity of an unknown.

This is a 1:1 titration. One mole of base will titrate one mole of acid. The endpoint of the titration will be determined by an indicator, phenolphthalein. Phenolphthalein is a weaker acid than KHP. It is colorless under acidic conditions and changes to a pink color under basic conditions. Therefore, the first persistent presence of color indicates that it is beginning to titrate the indicator and have reached the endpoint; if the solution changes to a dark pink color, the solution has overshot the endpoint. The formula of KHP is C8H5O4K.

In this experiment, a sample of KHP of unknown purity will be analyzed by titration with a standardized NaOH solution. The reaction is shown below:

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...Experiment 5- Standardization of NaOH and determination of Molarity of an unknown Acid
Objectives
1. Preparation and standardization of a 0.1M NaOH solution
2. To learn the technique of titration
3. Determination of the concentration of an unknown diprotic acid.
Introduction
Titration can be traced to the origins of volumetric analysis, which began in the late eighteenth century. Study of analytical chemistry began in France and the first burette was made by Francois Antoine Henri Descroizilles. The field began to spread to neighboring countries and eventually to the whole world. Titration can be defined as the gradual addition of one solution to another until the chemical amount of one reactant being added matches stoichiometrically the amount of another reactant in the solution initially present. Learning the right technique of Titration is essential because of its wide applications in all areas of science, it is used in laboratory medicine to determine unknown concentrations of chemicals of interest in blood and urine. Pharmacists also use titration in the development of new pharmaceuticals. Titration may also be used to determine the amount of a certain chemical in food. Often, titration is used to determine fat content, water content, and concentrations of vitamins. It is also used to tell if cheeses and wines have aged enough for distribution to supermarkets and shops....

...Titration Lab of NaOH and KHP
Aim: To titrate Sodium Hydroxide with Potassium Hydrogen Phthalate . To also determine the concentration of NaOH in the KHP solution.
Hypothesis: When KHP is added to the solution of NaOH and the indicator, the solution will turn clear and neutralize. The concentration of NaOH is going to be very low because it is diluted.
Materials required: pipette filler, volumetric flasks(2-4), beakers(2),small white piece of paper, indicator( 2 drops), conical flask, clamp, soap, eye protection, burette, distilled water, cleaning utensils, stand, funnel, solutions( NaOH and KHP)
Procedure:
1. Gathered all materials required
2. Wore proper safety equipment
3. All the equipment was washed and gathered.
4. The base (NaOH) and the acid (KHP) were labeled and put into conical flasks and beakers.
5. A rod was screwed into the hole which is in the desk. Also a clamp was placed on the rod.
7. The burette was placed on the clamp.
8. The funnel was rinsed with some acid (KHP) from the inside as well as the outside.
9. A very little amount of acid was poured into the burette to clean it and a beaker was placed underneath the burette.
10. The burette was opened from the bottom to let the acid fall out.
11. A funnel was placed on top of the burette, and a piece of paper was placed...

...20216815
EXPERIMENT A.1.1.2
THE PREPARATION AND STANDARDIZATION OF NaOH AND HCL SOLUTION
AIMS & OBJECTIVES:
(1) To gain experience with titration procedure
(2) To learn to standardize acid & base solution
(3) To carry out the preparation of solution of a desired concentration
(4) To carry out the preparation of solutions of desired concentration from more concentrated solution
INTRODUCTION:
Titration is a convenient quantitative method for accurately determining unknown concentrations of solutions. A necessary requirement for its use is that a standard solution (a solution of known concentration) reacts chemically with the solution whose concentration is being determined. The standard solution is added to a solution of unknown concentration until all of the unknown solution has reacted. From the known quantity and molarity (or normality) of the standard solution and the measured volume of unknown solution used, the unknown concentration can be calculated. For example, standard base solution (NaOH) is added from a burette to an accurately known volume of the acid solution (HCl).
CHEMICALS/EQUIPMENT:
Burette, retort stand & clamp, pipette, measuring cylinder, 500ml volumetric flask, 3 conical flasks, methyl orange,2g of NaOH salt,12M HCl,0.3g of oxalic acid dehydrate, distilled water, wash bottle ,analytical balance.
PROCEDURE (A): TITRATION OF 0.1...

...﻿Standardization of a NaOH Solution with Potassium Hydrogen Phthlate (KHP)
Name:________________________________________________________________ Period:_____
Prelab
1. A 0.8234-g sample of "KHP" required 38.76 mL of NaOH for titration to the phenolphthalein endpoint. What is the exact molarity of the NaOH solution?
2. A 25.00-mL aliquot of an unstandardized HCl solution is titrated with the previously standardized NaOH solution from #1 above. If 32.55 mL of NaOH titrant is required to reach the endpoint, what is the exact molarity of the HCl solution?
3. How accurately can you estimate the buret reading on a 50-mL buret that has calibration markings every 0.1mL? (Circle the correct answer)
a) 1 mL b) 0.1 mL c) 0.01 mL d) 0.001 mL
4. Why should the sample size be such that not more than 50 mL of titrant is required to reach the endpoint?
5. What mass (in grams) of "KHP" should be used for the standardization of a NaOH solution that is approximately 0.14 MNaOH if the volume of NaOH titrant used is to be about 45 mL? (Approximate calculation - 2 sig. figs is adequate)
Standardization of a NaOH Solution with Potassium Hydrogen Phthalate (KHP)
Objective...

...EXPERIMENT 2: SOLUTION PREPARATION AND STANDARDIZATION
Submitted by Iris Olaso
______________________________________________________________________________
INTRODUCTION
Generally, there are two ways in preparing a solution, one is by dissolving a weighed amount of solid in a required solvent and the other is by dilution of a concentrated solution into the desired concentration.
In diluting concentrated solution, the concentration of the diluted solution can be determined by standardization. To standardize a solution, we will need to perform titration. In this experiment, we will standardize acid and base solutions.
In this experiment, the students to students will be able to know the proper way of preparing solutions from solid and liquid reagents by using the proper pieces of glassware and equipment and to calculate the exact concentration of the prepared solution from standardization.
PROCEDURE
The reagents that were used in this experiment were concentrated hydrochloric acid, sodium hyrdoxide, sodium carbonate, potassium acid phthalate and phenolphthalein as indicator.
The pieces of glassware that were used to perform this experiment were volumetric flasks, Erlenmeyer flasks, beakers, volumetric pipette, burette, spatula and droppers. Also, the pieces of equipment that were used were analytical balance, top-loading balance and hot plate.
Preparation of 250 mL...

...EXPERIMENT 10
Volumetric Analysis I
Standardization of NaOH Solution
Outcomes
After completing this experiment, the student should be able to:
1.
2.
3.
4.
Demonstrate the concept of quantitative analysis.
Make solution and standardize it.
Explain the difference between primary and secondary standard solutions.
Quantitatively determine the concentration of a base.
Introduction
Titration is a common method of quantitative analysis used to determine the concentration of
an unknown substance in a solution. The method is easy to use if the quantitative relationship
between two reacting solutions is known. It is particularly well-suited to acid-base and
oxidation-reduction reactions. In this course, we will analyze commercial products such as
household vinegar and bleach.
In the case of acid-base titrations, these permit the determination of concentrations of unknown
acids or bases with a high degree of accuracy. In order to analyze unknown acids or bases, we
must have a “standard solution” to react with the unknowns. A standard solution is one in
which the concentration is accurately known. We will first prepare a standard solution of
NaOH. One way to prepare a standard solution is to dissolve an accurately massed amount of
the substance and dilute it to a measured volume. In this way, the concentration can be
calculated exactly. However, it is usually impossible to obtain NaOH of sufficient purity to use
it as a primary...

...﻿Title: Preparation and Standardization of a Sodium Hydroxide Solution
Objective/Purpose: The objective of this experiment will be the standardization of sodium hydroxide using potassium hydrogen phthalate by the titration method.
Introduction:
The concentration of solutions can be reported in terms of molarity and normality. Molarity is equal to: HCL, HBR, H2SO4, HNO3
M = mol Solute (mol) (Monoprotic) (Diprotic)
_______________
V(L)g solutions (L)
M = __N___ for Monoprotic acids molarity = normality molar mass
V
One molar solution can be prepared by dissolving the mass of 1 mole of the particular substance in enough water to make a 1L solution.
Monoprotic:
HCL + NaOH  H2O + NaCl
Diprotic:
H2SO4 + NaOH  H2O + Na2SO4
N = __EW__
L EW= molar mass L = number of titratable protons
To perform an acid-base neutralization using the titration technique to determine the concentration (normality) of the NaOH prepared in part A.
C8H5O4K + NaOH H2O + KC8H4O4Na
KHP: KHC8H4O4
*Acid base indicator- substances that have different colors in acidic and basic environments
*Phenolphthalein- colorless in acid and pink in base. The end point of the titration is the first permanent color change.
Materials:
-Sodium...